Patient-specific glenoid guides

ABSTRACT

A glenoid guide has an upper surface and a lower surface, wherein the lower surface is a patient-specific surface configured as a negative surface of a glenoid face based on a three-dimensional image of a shoulder joint of a patient reconstructed preoperatively from image scans of the shoulder joint of the patient. The glenoid guide includes an anatomic tubular drill guide extending from the upper surface along an anatomic alignment axis configured preoperatively with a patient-specific orientation and insertion location for guiding a glenoid implant into the glenoid face for anatomic shoulder arthroplasty. The glenoid guide includes a reverse tubular drill guide extending from the upper surface along a reverse alignment axis configured preoperatively with a patient-specific orientation and insertion location for guiding a glenoid baseplate into the glenoid face for reverse shoulder arthroplasty.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/098,625 filed Apr. 14, 2016, now issued as U.S. Pat. No. 10,426,493,which is a continuation of U.S. patent application Ser. No. 13/653,868filed Oct. 17, 2012, now issued as U.S. Pat. No. 9,351,743, which claimsthe benefit of U.S. provisional application No. 61/552,071 filed Oct.27, 2011. The disclosure of the above application is incorporated hereinby reference.

This application is related to the following concurrently filed UnitedStates patent applications, each of which is incorporated herein byreference: “Patient-Specific Glenoid Guide” U.S. application Ser. No.13/653,878, now issued as U.S. Pat. No. 9,451,973; “Patient-SpecificGlenoid Guide and Implants” U.S. application Ser. No. 13/653,886, nowissued as U.S. Pat. No. 9,554,910 and “Methods for Patient-SpecificShoulder Arthroplasty” U.S. application Ser. No. 13/653,893, now issuedas U.S. Pat. No. 9,301,812.

INTRODUCTION

In shoulder arthroplasty various guides and instruments are used todetermine an alignment axis and guide an implant for anatomic or reverseshoulder arthroplasty. The present teachings provide variouspatient-specific and other instruments for use in shoulder arthroplasty.

SUMMARY

The present teachings provide various patient-specific instruments foranatomic and reverse shoulder arthroplasty.

The present teachings provide a glenoid guide that has an upper surfaceand a lower surface. The lower surface is a patient-specific surfaceconfigured as a negative surface of a glenoid face (or glenoid cavity)based on a three-dimensional image of a shoulder joint of a patientreconstructed preoperatively from image scans of the shoulder joint ofthe patient. The glenoid guide includes an anatomic tubular drill guideextending from the upper surface along an anatomic alignment axisconfigured preoperatively with a patient-specific orientation forguiding a glenoid implant into the glenoid face for anatomic shoulderarthroplasty. The glenoid guide also includes a reverse tubular drillguide extending from the upper surface along a reverse alignment axisconfigured preoperatively with a patient-specific orientation andlocation for guiding a glenoid baseplate into the glenoid face forreverse shoulder arthroplasty.

In some embodiments, the glenoid guide can include a patient-specificperipheral surface forming a lip configured as a negative of a glenoidrim of the patient. The lip includes a through slot configured forviewing and marking the glenoid face.

In some embodiments, the glenoid guide can include a patient-specificperipheral surface portion configured as a negative of a coracoidsurface of the patient.

In some embodiments, the glenoid guide can be used with a drill guideconfigured to engage a baseplate implant for reverse arthroplasty. Thedrill guide includes a central tubular drilling post having apatient-specific location and a patient-specific drilling axis orientedalong the reverse alignment axis. The central tubular drilling post canbe configured to have a patient-specific height for controlling drillingdepth therethrough. The drill guide can also include peripheral drillingposts with patient-specific drilling axes. A drill having a stopconfigured to engage the central drilling post for controlling drillingdepth there through can be included with the glenoid guide and the drillguide.

Further areas of applicability of the present teachings will becomeapparent from the description provided hereinafter. It should beunderstood that the description and specific examples are intended forpurposes of illustration only and are not intended to limit the scope ofthe present teachings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present teachings will become more fully understood from thedetailed description and the accompanying drawings.

FIG. 1 is an exploded view of a prior art implant for reverse shoulderarthroplasty;

FIG. 2 is an environmental view of the prior art implant of FIG. 1;

FIG. 3A is an environmental view illustrating a guiding pin used duringreaming in reverse shoulder arthroplasty;

FIG. 3B is an environmental view illustrating a guiding pin afterreaming in reverse shoulder arthroplasty;

FIG. 4 is a perspective view of a prior art implant for anatomicshoulder arthroplasty;

FIG. 5 is perspective bottom view of a patient-specific glenoid guidefor reverse and anatomic shoulder arthroplasty according to the presentteachings;

FIG. 6 is perspective top view of the patient-specific glenoid guide ofFIG. 5;

FIG. 7 is perspective front environmental view of the patient-specificglenoid guide of FIG. 5;

FIG. 8 is perspective back environmental view of the patient-specificglenoid guide of FIG. 5;

FIG. 9 is a perspective view of a baseplate implant for the glenoidface;

FIG. 10 is a perspective view of a patient-specific secondary drillguide for use in reverse arthroplasty according to the present teachingsand shown with the baseplate of FIG. 9; and

FIG. 11 is a perspective view of the secondary drill guide of FIG. 10shown with a drilling tool having a depth stop.

Corresponding reference numerals indicate corresponding parts throughoutthe several views of the drawings

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is in no wayintended to limit the present teachings, applications, or uses.

The present teachings generally provide patient-specific surgicalinstruments that include, for example, alignment guides, drill guides,and other tools for use in shoulder joint replacement, shoulderresurfacing procedures and other procedures related to the shoulderjoint or the various bones of the shoulder joint, including the glenoidface or cavity of the scapula, the humeral head and adjacent shoulderbones. The present teachings can be applied to anatomic shoulderreplacement and reverse shoulder replacement. The patient-specificinstruments can be used either with conventional implant components orwith patient-specific implant components and/or bone grafts that areprepared using computer-assisted image methods according to the presentteachings. Computer modeling for obtaining three-dimensional images ofthe patient's anatomy using medical scans of the patient's anatomy (suchas MRI, CT, ultrasound, X-rays, PET, etc.), the patient-specificprosthesis components and the patient-specific guides, templates andother instruments, can be prepared using various commercially availableCAD programs and/or software available, for example, by Object ResearchSystems or ORS, Montreal, Canada.

The patient-specific instruments and any associated patient-specificimplants and bone grafts can be generally designed and manufacturedbased on computer modeling of the patient's 3-D anatomic image generatedfrom medical image scans including, for example, X-rays, MRI, CT, PET,ultrasound or other medical scans. The patient-specific instruments canhave a three-dimensional engagement surface that is complementary andmade to substantially mate and match in only one position (i.e., as asubstantially negative or mirror or inverse surface) with athree-dimensional bone surface with or without associated soft tissues,which is reconstructed as a 3-D image via the aforementioned CAD orsoftware. Very small irregularities need not be incorporated in thethree-dimensional engagement surface. The patient-specific instrumentscan include custom-made guiding formations, such as, for example,guiding bores or cannulated guiding posts or cannulated guidingextensions or receptacles that can be used for supporting or guidingother instruments, such as drill guides, reamers, cutters, cuttingguides and cutting blocks or for inserting guiding pins K-wire or otherfasteners according to a surgeon-approved pre-operative plan.

In various embodiments, the patient-specific instruments of the presentteachings can also include one or more patient-specific tubular guidesfor receiving and guiding a tool, such as a drill or pin or guide wireat corresponding patient-specific insertion points and orientationsrelative to a selected anatomic or reverse axis for the specificpatient. The patient-specific instruments can include guiding ororientation formations and features for guiding the implantation ofpatient-specific or off-the-shelf implants associated with the surgicalprocedure. The geometry, shape and orientation of the various featuresof the patient-specific instruments, as well as various patient-specificimplants and bone grafts, if used, can be determined during thepre-operative planning stage of the procedure in connection with thecomputer-assisted modeling of the patient's anatomy. During thepre-operative planning stage, patient-specific instruments, custom,semi-custom or non-custom implants and other non-custom tools, can beselected and the patient-specific components can be manufactured for aspecific-patient with input from a surgeon or other professionalassociated with the surgical procedure.

In the following discussion, the terms “patient-specific”, “custom-made”or “customized” are defined to apply to components, including tools,implants, portions or combinations thereof, which include certaingeometric features, including surfaces, curves, or other lines, andwhich are made to closely conform substantially as mirror-images ornegatives or complementary surfaces of corresponding geometric featuresor anatomic landmarks of a patient's anatomy obtained or gathered duringa pre-operative planning stage based on 3-D computer images of thecorresponding anatomy reconstructed from image scans of the patient bycomputer imaging methods. Further, patient-specific guiding features,such as, guiding apertures, guiding slots, guiding members or otherholes or openings that are included in alignment guides, drill guides,cutting guides, rasps or other instruments or in implants are defined asfeatures that are made to have positions, orientations, dimensions,shapes and/or define cutting planes and axes specific to the particularpatient's anatomy including various anatomic or mechanical axes based onthe computer-assisted pre-operative plan associated with the patient.

The patient-specific guides can be configured to mate in alignment withnatural anatomic landmarks by orienting and placing the correspondingalignment guide intra-operatively on top of the bone to mate withcorresponding landmarks. The anatomic landmarks function as passivefiducial identifiers or fiducial markers for positioning of the variousalignment guides, drill guides or other patient-specific instruments.

The various patient-specific alignment guides can be made of anybiocompatible material, including, polymer, ceramic, metal orcombinations thereof. The patient-specific alignment guides can bedisposable and can be combined or used with reusable and nonpatient-specific cutting and guiding components.

More specifically, the present teachings provide various embodiments ofpatient-specific glenoid guides and secondary drill guides for anatomicand reverse arthroplasty. The glenoid guides of the present teachingscan have patient-specific engagement surfaces that reference variousportions of the shoulder joint and include tubular drill guides, guidingbores or sleeves or other guiding formations that can accuratelyposition a guide wire for later glenoid preparation and implantationprocedures and for alignment purposes, including implant positioncontrol, implant version control, implant inclination control for bothanatomic and reverse arthroplasty.

In the following, when a portion of a glenoid guide is described as“referencing” a portion of the anatomy, it will be understood that thereferencing portion of the glenoid guide is a patient-specific portionthat mirrors or is a negative of the corresponding referenced anatomicportion.

In some embodiments, the glenoid guide can reference (substantially as anegative of) the face of the glenoid or glenoid cavity, avoiding theglenoid rim and any portion of the labrum. In other embodiments, theglenoid guide can reference (substantially as a negative of) the face ofthe glenoid and a portion of the glenoid rim. The glenoid guide can bedesigned to only remove a portion of the labrum (from 2-5 o'clock, forexample) or the entire labrum. When the glenoid guide is designed to sitdirectly on bone rather than soft tissue, then the labrum is removed. Inother embodiments, the glenoid guide can reference the labrum itself,such as when MRI scans are used to reconstruct details of the geometryof the soft tissue and the glenoid guide is designed references off softtissue. In other embodiments, the glenoid guide can reference theglenoid face and a portion of the coracoid process or coracoidattachment that extends off the upper aspect of the glenoid.

In some embodiments the glenoid guide can have built-in holes, openingsor windows that would allow the surgeon to mark the glenoid bone or amodel of the glenoid bone with a marking pen, burr, scalpel, or anyother device that can create markings to be used as landmarks on or inthe glenoid bone or glenoid model. These landmarks can be used for theorientation of a secondary guide. The glenoid guide can also provide away to physically mark the glenoid bone for proper orientation ofadditional glenoid guides via a plurality of slits to be used to passmarking tools.

The various glenoid guides described herein can include a plurality ofdrill guide formations, holes or bores for placing various alignmentguide wires or pins or for drilling. In some embodiments, the glenoidguide can include a second drill or guide wire bore, for example, with a10-degree or other inferior tilt (and possibly shifted superiorly orinferiorly) to accommodate proper baseplate placement for use with areverse shoulder arthroplasty. Peripheral drill holes for use with areverse baseplate can also be included. Accordingly, these features ofthe glenoid guide allow a surgeon to use the glenoid guide for either ananatomic or reverse shoulder arthroplasty. As discussed below, thevarious additional holes or bores can orient the drill holes that aredrilled before implantation of the baseplate screws. The additionalholes can be oriented to position each baseplate screw in the bestavailable bone stock and can control the depth of the screw hole. Thedepth would be controlled by bosses built onto the guide. A mating drillcan be used with a physical stop built into it. The stop would referencethe boss built onto the guide therefore accurately controlling the depthof the screw hole.

Referring to FIGS. 1-3, a prior art reverse shoulder implant 100 isillustrated. The reverse shoulder implant 100 includes a humeral stem102, a humeral tray 107, a humeral bearing 110, a glenosphere 111 and abaseplate 124 having a plate portion 126 and a central boss 128. Thehumeral stem 102 is implanted in the humeral bone 70 and has a proximalend 104 coupled via a Morse taper connection to a male taper 108extending from a plate 106 of the humeral tray 107. The glenosphere 111can be modular and include a head 112 articulating with the bearing 110and an offset double-taper component 115. The double-taper component 115has a first tapered portion 114 coupled to a corresponding taperedopening 113 of the head 112 and a second tapered portion 116 coupled tothe central boss 128 of the glenoid baseplate 124. A central screw 118passes through the baseplate 124 into the glenoid face 80 of thepatient's scapula. Peripheral screws 120 are used to lock the baseplate124 in the glenoid face 80. FIG. 3A illustrates using a guiding pin 150to guide reaming of the glenoid face 80 in reverse shoulder arthroplastyusing a reamer 130. FIG. 3B illustrates the guiding pin 150 through ahole 90 drilled through the glenoid face 80. The guiding pin 150 is usedto guide placement of a reverse or anatomic implant, as discussed below.

Referring to FIG. 4, a prior art anatomic shoulder implant 180 isillustrated. The anatomic shoulder implant 100 includes a humeral stem182, a glenosphere 184 and a bearing 186 with peripheral pegs 190 and aremovable or non-removable central peg 188.

Referring to FIGS. 5-8, a patient-specific glenoid guide 200 isillustrated. The patient-specific glenoid guide 200 is configured toguide a guiding pin (such as the guiding pin 150 shown in FIGS. 3A and3B) and provide an implant alignment orientation for reverse as well asanatomic shoulder arthroplasty at the surgeon's discretion. The glenoidguide 200 has an upper (or outer) surface 202 and a lower (or inner) oranatomy-engaging and patient-specific surface 204 that references(substantially as a negative or inverse or mirror) the glenoid face 80and may include all or a portion of the labrum 82, i.e., the peripheralcartilaginous structure that encircles and deepens the glenoid face 80.Alternatively, the labrum 82 can be completely removed such that thepatient-specific glenoid surface 204 references and mirrors only thebone surface of the glenoid cavity or glenoid face 80. Optionally, theglenoid guide 200 can include a peripheral portion or peripheral lip 206with a corresponding patient-specific peripheral surface 205 thatengages a corresponding peripheral surface or glenoid rim 84 around thescapula of the patient. A first (or anatomic) elongated tubular drillguide 216 can extend from the upper surface 202 of the glenoid guide 200at a specific location and along a first axis A that is determined anddesigned according to the pre-operative plan of the patient to define apatient-specific anatomic alignment axis and insertion point for aguiding pin 150. A second (or reverse) elongated tubular drill guide 214can extend from the upper surface 202 of the glenoid guide along asecond axis B that is determined and designed according to thepre-operative plan of the patient to define a patient-specific reversealignment axis and insertion point for a guiding pin 150. The reversealignment axis B can have a predetermined inferior tilt relative to theanatomic alignment axis A, such as, for example, a ten-degree inferiortilt. The first and second drill guides 216, 214 define correspondingelongated bores 224 and 222 for guiding a drill bit and/or inserting analignment pin or guiding pin 150. Each drill guide 216, 214 can includeelongated openings or viewing windows 226 therethrough. The anatomicdrill guide 216 and the reverse drill guide 214 can includecorresponding visual and/or tactile markings 220, 218 indicating theircorresponding functions for easy identification and to avoid confusion.The markings can be, for example, elevated lettering using the wordsANATOMIC for marking 220 and REVERSE for marking 218. Additionally,marking 219 can be provided with other patient-specific information,such as, for example, patient identification, procedure, etc. Theanatomic and reverse drill guides 216, 214 can be connected with a webor flange 230 for additional stability and can be either removablycoupled (via a snap-on or a threaded connection, for example) to theglenoid guide 200 or fixedly attached to the glenoid guide 200.

With continued reference to FIGS. 5-8, the patient-specific glenoidguide 200 can include a patient-specific outer surface portion 212 thatcan reference a corresponding surface portion 86 of the coracoid process88 or the coracoid attachment. The patient-specific glenoid guide 200can also include a slot 208 through the peripheral lip 206 for viewingand optionally marking by the surgeon. The surgeon can, for example, fitthe patient-specific glenoid guide 200 over a patient-specific bonemodel of the patient and mark the bone model through the slot 208. Thepatient-specific bone model is also constructed during the samepreoperative plan from the 3-D images of the joint from which thepatient-specific glenoid guide 200 is designed and constructed. Thesurgeon can view the marked bone model and be guided for approximatepositioning of the glenoid guide on the patient's bone. The glenoidguide 200, of course, will only fit on the bone uniquely (only in oneposition, unique fit). The marking will expedite the placement of thepatient-specific glenoid guide 200 without unnecessary trials to findthe single fit location. The patient-specific glenoid guide 200 can alsoinclude a block (or other holder) 210 extending above the upper surface202 and configured to allow the surgeon to hold and stabilize thepatient-specific glenoid guide 200. The block 210 can be sized andshaped to accommodate a thumb or one or more fingers of the surgeon.

Additionally, the patient-specific glenoid guide 200 can include aperipheral alignment notch 223 that can be used to mark the glenoidsurface. The marking made through the notch 223 can be used with aprojection 321 of a secondary drill guide 320 for rotational alignmentof the secondary drill guide 320, as discussed below in reference toFIGS. 10 and 11.

Referring to FIGS. 3A, 3B, 4 and 7, the glenoid guide 200 can be usedfor anatomic arthroplasty to drill a hole 90 into the glenoid face 80through the anatomic drill guide 216 and insert a guiding pin or otherK-wire 150. The guiding pin 150 can be used to guide the predeterminedalignment of the bearing 186 in the glenoid face 80 for implantation inanatomic arthroplasty.

Referring to FIGS. 2, 3A, 3B and 7, in reverse arthroplasty, the glenoidguide 200 can be used to drill a hole 90 into the glenoid face 80through the reverse drill guide 214 to insert a guiding pin or otherK-wire 150. The guiding pin 150 can be used to guide the predeterminedalignment of the baseplate 124 shown in FIG. 2 (or baseplate 300 shownin FIG. 9 and discussed below) in the glenoid face 80 for implantationin reverse arthroplasty.

Additionally, and with reference to FIGS. 9-11, a secondary drill guide320 can be used to drill screw holes for baseplate fixation. Thesecondary drill guide 320 can be attached to a baseplate 300 of areverse shoulder arthroplasty implant and provide drill holetrajectories that position the fixation screws along paths that arepreoperatively determined to have the best bone stock, such as healthycortical bone, in terms of strength, accessibility and other factors.The secondary drill guide 320 can be assembled onto the baseplate 300after the baseplate 300 has been impacted into the glenoid.Alternatively, the secondary drill guide 320 may be attached to thebaseplate 300 during impaction. The secondary drill guide 320 caninclude a projection 321 which is aligned with the marking made throughthe peripheral alignment notch 223 of the patient-specific acetabularguide 200 to orient the secondary drill guide 320 according to thepreoperative plan for the procedure.

The baseplate 300 can include an upper face 306, a central hole 304passing through a central fixation peg 308 of the baseplate 300 and aplurality of peripheral fixation holes 302 (four holes are shown in FIG.9). The secondary drill guide 320 has an upper face 322 and an oppositeface mating with the upper face 306 of the baseplate 300. A central post(or boss) 326 with a through bore 325 and a plurality of peripheralposts 324 with corresponding through bores 323 extend from the upperface 322 of the secondary drill guide 320 and communicate with thecorresponding central hole 304 and peripheral fixation holes 302 of thebaseplate 300.

The secondary drill guide 320 can control drill orientation via holesthat are pre-drilled through the bores 323 of secondary drill guide 320.The secondary drill guide 320 can control drill depth using controlledpost heights for the posts 324, 326. The heights of the posts 324, 326(their length above the upper surface 322) and the drill orientationscan be determined and configured into the secondary drill guide 320during the pre-operative plan of the patient based on the 3-Dreconstructed images of the patient's shoulder joint. A mating drill 340with drill bit 342 can have a physical stop element 350, as shown inFIG. 11. The stop element 350 on the drill 340 and the patient-specificcontrolled post heights on the secondary drill guide 320 can providedepth control. The secondary drill guide 320 can be designed to ensurethat the fixation screws for the baseplate 300 achieve sufficientbi-cortical support.

The glenoid guide 200 of the present teachings can also provide aphysical stop for glenoid reaming. For example, depth of reaming can bedetermined preoperatively and a guide wire or guiding pin 150 can beinserted to the predetermined depth, see FIG. 3A. The reamer 130 can bemade to reference the guiding pin 150 such that the cutting depth of thereamer 130 is limited to the predetermined depth for both anatomic andreverse glenoid reaming.

Generally, the patient-specific glenoid guide 200 of the presentteachings references landmarks on the glenoid to orient the glenoidguide 200 in a predetermined orientation according to a preoperativeplan for the specific patient. Landmarks can include, for example, theglenoid face 80 with or without any portion of the labrum 82, thecoracoid process 88 (or portions thereof or coracoid attachment), theglenoid rim 84 and/or other landmarks of the scapula. Thepatient-specific glenoid guide 200 can be used to correctly orient aguide wire or guiding pin 150 that will be used in later glenoidpreparation procedures. The patient-specific glenoid guide 200 caninclude drill guides 214, 216 or similar elements that enable theglenoid guide 200 to be used for both anatomic and reverse shoulderreplacements. The glenoid guide 200 can also be designed so that it canorient a secondary glenoid drill guide.

Summarizing, the patient-specific glenoid guide 200 can be used toposition a guide wire at a predetermined orientation and location(insertion point) for use in an anatomic shoulder replacement (axis Ashown in FIG. 7) or reverse shoulder replacement (axis B shown in FIG.7). The patient-specific glenoid guide 200 can reference landmarks oneither the glenoid or the scapula to provide a secure foundation for thepatient-specific glenoid guide 200. The predetermined orientation can bedesigned and configured into the patient-specific glenoid guide 200 forimplant positioning, implant version control, and implant inclinationcontrol.

Various additional methods can be incorporated in the preoperative planfor accurate placement of the glenoid guide 200 and for positioning acentral guiding pin 150 through the glenoid for additional purposes,such as version, inclination, pin insertion point or other alignmentcontrol and guidance of the glenoid implants. As discussed above, thesemethods include identification of landmarks and software (or algorithms)used to position the guide pin as part of a preoperative plan for thespecific patient. The software and landmarks can be used to create thepatient-specific guide 200 or other similar guides for use duringshoulder surgery. The algorithms and surgeon inputs (defining slightadjustments to the algorithm for inferior/superior tilt, versioncontrol, and pin position) can be incorporated in specific preoperativesoftware that a surgeon can use interactively to create a virtualglenoid guide. The physical patient-specific glenoid guide 200 can bemanufactured preoperatively from the virtual glenoid guide with surgeoninput and can be used intraoperatively to accurately position theguiding pin 150 in the correct location/orientation through the glenoid.After the guiding pin 150 is placed, other glenoid preparationinstrumentation can used with reference to this guide pin. Thepreoperative plan can also provide the surgeon with details of theamount and shape of a bone graft or bone removal that can used tocorrect for natural version. Additionally, the preoperative plan can beused to properly orient and determine the length of the fixation screwsused in a reverse shoulder arthroplasty to ensure that the screws areanchored into the best available bone stock for the patient.

As described above, the patient-specific glenoid guide 200 can fitaround or on the exposed glenoid rim and surface substantially as anegative of the corresponding anatomy of the patient and includesguiding formations or drill guides for guiding theselected/predetermined orientation of the guiding pin for anatomic orreverse arthroplasty. Additionally, the glenoid guide 200 can matchdefects and imperfections in the specific patient's glenoid.

The patient-specific glenoid guide 200 can be used for both reverse andanatomic arthroplasty and can be used included in any anatomic orreverse arthroplasty kit with corresponding implants and otherinstruments. Additionally the patient-specific glenoid guide 200 can beincluded in an omnibus surgeon kit together with the reverse shoulderimplant 100, the secondary drill guide 320, the baseplate 300, and theanatomic shoulder implant 180 to allow the surgeon to switch betweenreverse and anatomic arthroplasty during the procedure.

For reverse shoulder procedures the patient-specific glenoid guide 200can incorporate via the corresponding reverse tubular drill guide 214 abuilt-in inferior tilt of the center guiding pin 150 for the orientationof the glenoid implant. An inferiorly tilted glenoid implant provides aproper range of motion and reduction of stresses around the implant.Additionally, the preoperative plan (i.e. the software, or applicationor data set or drawings and models used to prepare the preoperativeplan) can analyze the best bone stock and aim the peripheral and centralscrews toward the best bone stock. The preoperative plan can be alsoused to accurately determine proper screw length.

In some embodiments, the patient-specific glenoid guide can include anelevated block configured for stabilizing the glenoid guide using one ormore fingers, such as the thumb and or other fingers of the surgeon.

In some embodiments, interactive software can be used during thepreoperative plan for the patient can provide the surgeon with theamount of bone graft needed to restore natural version for a specificpatient. The interactive software can, for example, specify the numberof millimeters of bone graft to be added in the worn portion of theglenoid. The surgeon may also plan to ream a portion of the glenoid torestore version and have the amount of bone to be removed provided bythe interactive software.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the disclosure. Individual elements or featuresof a particular embodiment are generally not limited to that particularembodiment, but, where applicable, are interchangeable and can be usedin a selected embodiment, even if not specifically shown or described.The same may also be varied in many ways. Such variations are not to beregarded as a departure from the disclosure, and all such modificationsare intended to be included within the scope of the disclosure.

Example embodiments are provided so that this disclosure will bethorough, and will fully convey the scope to those who are skilled inthe art. Numerous specific details are set forth such as examples ofspecific components, devices, and methods, to provide a thoroughunderstanding of embodiments of the present disclosure. It will beapparent to those skilled in the art that specific details need not beemployed, that example embodiments may be embodied in many differentforms and that neither should be construed to limit the scope of thedisclosure. In some example embodiments, well-known processes,well-known device structures, and well-known technologies are notdescribed in detail.

What is claimed is:
 1. A patient-specific glenoid guide for guiding anobject toward a glenoid face of a scapula of a patient for implantationof a prosthetic device, the glenoid guide comprising: a patient-specificportion having at least one patient-specific surface that is configuredto nest and closely conform to a corresponding surface of the glenoidface to position the at least one patient-specific surface at apredetermined position relative to the glenoid face; a drill guideextending through the patient-specific portion along a first alignmentaxis configured preoperatively with a patient-specific orientation andinsertion location, wherein the insertion location is at the glenoidface; a feature offset from the drill guide and coupled to thepatient-specific portion and configured to be graspable by one or morefingers of a surgeon for stabilizing the glenoid guide, wherein thefeature comprises a block that is elevated from a side of thepatient-specific portion opposing the at least one patient-specificsurface; and a patient-specific peripheral surface forming a peripherallip configured as a negative of a glenoid rim of the patient, whereinthe block extends above and outward from the peripheral surface so as toextend past the glenoid rim.
 2. The glenoid guide of claim 1, whereinthe block is configured to be held or otherwise contacted by a thumb ofthe surgeon.
 3. The glenoid guide of claim 1, wherein the drill guidecomprises a first tube and a second tube projecting from thepatient-specific portion opposite the at least one patient-specificsurface, the first tube and the second tube disposed at an angle fromone another.
 4. The glenoid guide of claim 1, wherein the at least onepatient-specific surface is configured to engage and nest with ananterior rim of the glenoid face.
 5. The glenoid guide of claim 1,wherein the at least one patient-specific surface is configured to nestwith one or more of a superior, inferior and posterior portion of a rimof the glenoid face.
 6. The glenoid guide of claim 1, wherein thefeature extends above and outward of a portion of the patient-specificperipheral surface forming the lip.
 7. The glenoid guide of claim 1,further comprising a patient-specific peripheral surface portionconfigured as a negative of a coracoid surface of the patient.
 8. Theglenoid guide of claim 1, wherein the glenoid guide further includes analignment notch for marking the glenoid face.
 9. A glenoid guide forguiding an object toward a glenoid face of a scapula of a patient forimplantation of a prosthetic device, the glenoid guide comprising: aglenoid portion having a surface that is configured to interface with asurface of the glenoid face to position the glenoid portion relative tothe glenoid face; a drill guide extending through the glenoid portionand having one or more apertures to provide access at the glenoid face;and a feature offset from the drill guide and coupled to the glenoidportion wherein the feature is graspable by one or more fingers of asurgeon for stabilizing the glenoid guide, wherein the feature comprisesa block that is elevated from a side of the glenoid portion opposing thesurface, and wherein the block is configured to extend above and outwardof a portion of a periphery of the glenoid portion.
 10. The glenoidguide of claim 9, wherein the glenoid portion comprises apatient-specific portion having at least one patient-specific surfacethat is configured to nest and closely conform to a correspondingsurface of the glenoid face to position the at least onepatient-specific surface at a predetermined position relative to theglenoid face.
 11. The glenoid guide of claim 9, wherein the block isconfigured to be held or otherwise contacted by a thumb of the surgeon.12. A patient-specific glenoid guide for guiding an object toward aglenoid face of a scapula of a patient for implantation of a prostheticdevice, the glenoid guide comprising: a patient-specific portion havingat least one patient-specific surface that is configured to nest andclosely conform to a corresponding surface of the glenoid face toposition the at least one patient-specific surface at a predeterminedposition relative to the glenoid face; a drill guide extending throughthe patient-specific portion along a first alignment axis configuredpreoperatively with a patient-specific orientation and insertionlocation; a feature coupled to the patient-specific portion andconfigured to be graspable by one or more fingers of a surgeon forstabilizing the glenoid guide; and a patient-specific peripheral surfaceforming a lip configured as a negative of a glenoid rim of the patient,wherein the lip includes a through slot configured for viewing andmarking the glenoid face.